A novel covalent triazine framework (CTF-0) was prepared by trimerization of 1,3,5-tricyanobenzene in molten ZnCl 2 . The monomer/ ZnCl 2 ratio, the reaction time, and temperature significantly influence the structure and porosity of such networks. XRD measurements revealed that crystalline frameworks can be formed with surface areas around 500 m 2 •g −1 and high CO 2 uptakes. Increasing the reaction temperature yielded an amorphous material with an enlarged surface area of 2000 m 2 •g −1 . This material showed good catalytic activity for CO 2 cycloaddition.

An important goal in the preparation of highly active supported metal particles is the enhancement of the metal support interaction, providing a more stable catalyst, especially for liquid phase reactions as the leaching and reconstruction of the active phase causes deactivation. In this work, a covalent triazine framework (CTF) as support for Pd nanoparticles is compared to activated carbon (AC), the typical support used in liquid phase reactions. The results indicate that the presence of the N-heterocyclic moieties on the surface of the frameworks is beneficial for improving the stability of Pd nanoparticles during the liquid phase glycerol oxidation. Pd/CTF showed better activity and in particular better stability when compared to Pd supported on activated carbon (AC).

Mesoporous melamine resins have been prepared using hexamethoxymethyl melamine (HMMM) as monomer and block-co-polymer Pluronic F127 as template. At acidic conditions, HMMM condenses into melamine resins, replicating the mesophases formed by the block-co-polymer template. The template can be removed by solvent extraction, yielding mesoporous melamine resins with surface areas of up to 258 m 2 /g and pore diameters of 7.8 nm. At a HMMM/F127 weight ratio of 1:1 an ordered mesoporous melamine resin is observed exhibiting a 2d hexagonal arrangement of cylindrical pores. The simplicity of the synthesis of these mesoporous films allows the large scale production of the materials, for example, in the form of free-standing films.

Polymer composites are currently suggested for use as improved dielectric materials in many applications. Here, the effect of particle size and dispersion on the electrical properties of composites of rutile TiO2 and poly(styrene–ethylene–butadiene–styrene) (SEBS) are investigated. Both 15 and 300 nm particles are mixed with SEBS, with amounts of sorbitan monopalmitate surfactant from 0 to 3.3 vol%, and their dielectric and mechanical properties are measured. Composites with the 300 nm TiO2 particles result in increases of 170% in relative permittivity over the pure polymer, far above those predicted by standard theories, such as Bruggeman (140%) and Yamada (114%), and improving dispersion with surfactant has little effect. The composites with 15 nm particles showed surprisingly large relative permittivity increases (350%), but improving the dispersion by the addition of any surfactant causes the relative permittivity to decrease to 240% of the pure polymer value. We suggest that the increase is due to the formation of a highly conductive layer in the polymer around the TiO2 particles.

Abstract. Melamine-formaldehyde polymer was synthesized into the form of self-supporting films. The structural stability of these films was investigated by means of spectroscopy and thermal analysis. The curing temperature and time has effects on the structural stability of the resulting polymer films. In this work, polymer film cured at 200 oC for 12 hours showed highest structural stability compared to those cured at lower temperature and shorter time duration.

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